JP2715509B2 - Dielectric particle packed bed filter device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a dielectric particle packed bed filter device, and in particular, has a charging section for charging dust and bacteria contained in a gas at an inlet side of a gas flow. The dielectric particles are filled on the downstream side of the gas flow, a voltage is applied to the dielectric particle layer to collect dust and bacteria, and the bacteria collected by causing a partial discharge in the dielectric particle layer. The present invention relates to a dielectric particle-filled layer filter device that kills the particles.

[Conventional technology]

Conventionally, the dielectric particle layer portion of this type of dielectric particle filling layer filter device is formed by laminating dielectric particles having a diameter of about 2 mm as a layer having a thickness of about 20 mm, and wire mesh electrodes provided on both sides thereof.
It is configured to cause a partial discharge in the particle layer and to apply a high voltage in a range where flashover does not occur between the wire mesh electrodes. The high voltage applied to the wire mesh electrode is manually adjusted.

[Problems to be solved by the invention]

However, in the above configuration, current and flash voltage fluctuate due to dirt, temperature, and temperature of the dielectric particles, and the discharge state in the dielectric particle layer also changes. As a result, dust and bacteria are collected. However, there has been a drawback that the rate and the sterilization rate fluctuate, and flashover occurs continuously, making it impossible to operate the dielectric particle packed layer filter device.

The present invention has been made in view of such circumstances, and regardless of fluctuations in the current and flash voltage of the dielectric particle layer, the generation of flash and stable collection and sterilization of dust and bacteria are prevented. It is an object of the present invention to provide a dielectric particle packed layer filter device that can be used.

[Means to solve the problem]

In order to achieve the above object, the present invention has a charging unit for charging dust and bacteria contained in a gas at an inlet side of a gas flow, and filling dielectric particles on a downstream side of the gas flow with a dielectric particle. A voltage is applied to the particle layer to collect dust and bacteria, and the dielectric particle packed layer filter device kills the collected bacteria by causing a partial discharge in the dielectric particle layer. Voltage adjusting means for adjusting the voltage applied to the layer, detecting means for detecting a frequency component higher than a power supply voltage frequency in the current flowing through the dielectric particle layer, and current of the frequency component detected by the detecting means And control means for controlling the voltage adjusting means so as to make constant.

[Action]

The present invention focuses on that, when the voltage applied to the dielectric particle layer is increased, a partial discharge starts in the dielectric particle layer, and a pulse current composed of a frequency component higher than the power supply frequency is increased. Among the currents flowing through the dielectric particle layer, a current having a frequency component higher than the power supply frequency is detected so that the current value of the high frequency component becomes constant, that is, a constant partial discharge is caused, and flashover occurs. The voltage applied to the dielectric particle layer is automatically adjusted so as not to occur.

〔Example〕

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the dielectric particle packed layer filter device according to the present invention will be described below in detail with reference to the accompanying drawings.

First, the present invention will be described in principle. When the voltage applied to the dielectric particle layer is increased, a partial discharge starts in the dielectric particle layer and becomes stronger. When the voltage becomes higher than a certain level, flashover occurs between the electric field forming electrodes. Then, as the voltage increases, the collection rate of dust and bacteria increases, and when a partial discharge starts in the dielectric particle layer, the bacterial effect increases.

However, in a situation where the partial discharge is increased to some extent or a flashover occurs between the electric field forming electrodes, the dust collection rate is reduced.

Focusing on the current flowing through the dielectric particle layer at this time,
Until partial discharge occurs in the dielectric particle layer, a current having a waveform substantially similar to the power supply voltage waveform and corresponding to the capacitance and resistance of the dielectric particle layer flows.

On the other hand, when a partial discharge occurs, a pulse-shaped current C accompanying the partial discharge is superimposed on a power supply voltage waveform A shown in FIG. 2 (A) and a current waveform B shown in FIG. 2 (B). When the voltage is further increased, the number of pulses of the pulse current increases, and the peak value increases. When the voltage becomes higher than a certain level, flashover occurs between the electric field forming electrodes as described above.

From the above phenomena, in order to operate the dielectric particle packed bed filter device so as to exhibit high dust and bacteria collection performance and sterilization performance, the pulse current is detected and the value becomes a desired value. The applied voltage may be controlled.

FIG. 1 is a configuration diagram showing one embodiment of a dielectric particle packed layer filter device according to the present invention. In the figure, arrow 10
Indicates a flow of air (gas) containing dust, bacteria, and the like, and this gas flows into the outer cylinder 12 of the filter device.
In the outer cylinder 12, a discharge electrode 14, a dielectric particle filling layer filter 16 and a fan 18 are provided.

The dielectric particle-filled layer filter 16 is formed by filling dielectric particles 16A having a diameter of several millimeters made of a ferroelectric material such as barium titanate between two wire mesh electrodes (electric field forming electrodes) 16B and 16C in a layered manner. An AC voltage is applied between the two electric field forming electrodes 16B and 16C from an AC power supply 20 via a step-up transformer 22.

The discharge electrode 14 charges dust and bacteria in the gas by corona discharge, and is provided on the inlet side of the filter 16. A DC high-voltage power supply 24 is connected between the discharge electrode 14 and the electric field forming electrode 16B of the filter 16. The electric field forming electrode 16B is grounded.

The fan 18 discharges the air cleaned by the filter 16 to the outside of the apparatus, and is provided on the outlet side of the filter 16.

Accordingly, dust and bacteria in the gas flowing in the direction of arrow 10 are charged by corona discharge of discharge electrode 14 and reach dielectric particle packed layer filter 16. Dielectric particle packed layer filter 16
Each of the dielectric particles 16A is polarized by the voltage applied between the electric field forming electrodes 16B and 16C, an electric field is concentrated on a slight air of the adjacent dielectric particles 16A, and the applied electrode is connected to the electric field forming electrode 16B. , A much higher electric field is generated than the apparent electric field divided by the distance between 16C.

As a result, dust and bacteria charged by the corona discharge are efficiently collected by the dielectric particles 16A under the effect of the strong electric field.

As described above, when the voltage applied to the dielectric particle-filled layer filter 16 is increased, the collection rate of dust and bacteria is improved with the increase, and the voltage is partially increased in the dielectric particle-filled layer filter 16. When the discharge starts, the germicidal effect is greatly increased, but the dust collection rate is reduced in a situation where the partial discharge is intensified to some extent or a flashover occurs between the electric field forming electrodes 16B and 16C.

Next, a device for automatically adjusting the voltage applied between the electric field forming electrodes 16B and 16C to an optimum value according to the present invention will be described. This device includes a current detection unit 30, a pulse component detection unit 32, a comparison operation unit 34, a pulse current value setting unit 36, and a voltage adjustment unit 38.

The current detection unit 30 detects the ground current of the step-up transformer 22, and detects this ground current, that is, the dielectric particle packed layer filter 16
Is applied to the pulse component detection unit 32.

The pulse component detection unit 32 is generated in the dielectric particle filling layer filter 16 except for the component having the same component as the output voltage waveform of the step-up transformer 22 included in the input signal, that is, the component having the same component as the frequency of the AC power supply 20. Only the pulse current component due to the partial discharge is extracted, and a signal proportional to the intensity is added to the comparison operation unit.

The set value signal from the pulse current value setting unit 36 is applied to the other input of the comparison operation unit 34. That is,
The pulse current value setting unit 36 is appropriately set so as to output a signal of the same level as the output signal of the pulse component detection unit 32 when the collection rate of dust and bacteria is highest.

The comparison operation unit 34 compares the two input signals and outputs a signal for increasing the voltage to the voltage adjustment unit 38 when the pulse current value is smaller than the set value, and when the pulse voltage value is larger than the set value. , A signal for lowering the voltage is output to the voltage adjustment unit 38.

The voltage adjusting unit 38 adjusts the voltage applied to the dielectric particle-filled layer filter 16 by the signal applied from the comparison operation unit 34, so that the partial discharge in the dielectric particle-filled layer filter 16 becomes constant. Controlled.

In this embodiment, the voltage applied to the dielectric particle-filled layer filter is an alternating current, but may be a direct current.

〔The invention's effect〕

As described above, according to the dielectric particle-filled layer filter device of the present invention, it is possible to stably apply a voltage optimal for collecting dust and bacteria and sterilizing the dielectric particle-filled layer filter. And the best performance.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of a dielectric particle packed layer filter device according to the present invention, and FIGS. 2 (A) and 2 (B) each show partial discharge generated in the dielectric particle packed layer filter. FIG. 3 is a voltage waveform diagram and a current waveform diagram when the power is on. 14 ... discharge electrode, 16 ... dielectric particle packed layer filter, 20 ...
... AC power supply, 30 ... current detection unit, 32 ... pulse component detection unit, 34 ... comparison operation unit, 36 ... pulse current value setting unit, 38 ... voltage adjustment unit.

Claims (1)

(57) [Claims] 1. A charging section for charging dust and bacteria contained in a gas at an inlet side of a gas flow, filling dielectric particles on a downstream side of the gas flow, and applying a voltage to a dielectric particle layer. In the dielectric particle filling layer filter device that collects dust and bacteria and kills the collected bacteria by causing a partial discharge in the dielectric particle layer, the voltage applied to the dielectric particle layer is Voltage adjusting means for adjusting, of the current flowing through the dielectric particle layer, detecting means for detecting a frequency component higher than a power supply voltage frequency, so that the current of the frequency component detected by the detecting means is constant. Control means for controlling the voltage adjusting means; and a dielectric particle packed layer filter device.